Pension and Other Postretirement Benefit Plans - Components of Net Periodic Expense (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Pension [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service Cost	$ 9.9		$ 9.1	$ 7.6
Interest Cost	26.0		26.4	27.4
Expected Return on Plan Assets	(35.2)		(35.4)	(34.6)
Amortization of Loss	21.5		17.5	12.1
Amortization of Prior Service Cost (Credit)	0.3		0.3	0.3
Net Expense (Credit)	22.5		17.9	12.8
Postretirement Health and Life [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service Cost	3.9		4.2	3.8
Interest Cost	6.8		9.4	10.8
Expected Return on Plan Assets	(9.7)		(9.9)	(9.7)
Amortization of Loss	1.6		7.5	8.5
Amortization of Prior Service Cost (Credit)	(2.5)		(1.7)	(1.7)
Amortization of Transition Obligation	0		0.1	0.1
Effect of Plan Settlement	(1.6)	[1]	0	0
Net Expense (Credit)	$ (1.5)		$ 9.6	$ 11.8

[1] Result of the exit from a legacy benefit plan.